My attempt to this question was checking the stability of carbocation. As III has a possibility of 3* carbocation with dancing resonance (hence most stable) it would have the highest rate.
How do I decide between (I) and (II) as both have 2-degree carbocation possibility with dancing resonance
Carbocation formed at (I) would have 4 alpha Hydrogen whereas carbocation formed at (II) would have 3 alpha hydrogen hence according to this logic I am getting the order II<I<III.
But we can also argue that (II) will have 2 positions at which carbocation can form hence higher rate that (I). Which factor would dominate and why?
(PS: answer given in my book is I<II<III)